In the construction trades the need often arises to establish a reference line which is level or a reference line which is plumb and to this end various devices have been developed for establishing such reference lines. One of the most common devices for establishing a reference line is the carpenter's level.
The carpenter's level has at least one reference edge and one or more bubble vials for correctly aligning the reference edge along a true horizontal or vertical line. Carpenter's levels are commonly available in various lengths ranging from about eight inches up to about forty-eight inches. While levels in the common range of lengths are suitable for most tasks, the need often arises for a level of extended length, such as a level of over forty-eight inches in length. Levels of extended length are not widely available and those which are available tend to be expensive on account of their unusual size. In addition, levels of extended length are unwieldy due to their size and present problems in transport and storage.
It is well-known that even though the carpenter's level is a valuable and oftentimes costly tool, it is subject to the vicissitudes of use. Bumping and jarring in the course of everyday handling can cause the bubble vials of the level to become misaligned with respect of the reference edge, thereby degrading the accuracy of the level and ultimately its usefulness.
In view of the need for a level of extended length and versatility and the drawbacks associated with such levels as are presently known in the art and the need for maintaining the accuracy of such a level, the inventor has developed the present invention.